The method for forming a coating of the present invention includes: a first step of applying a first solution containing a polysilazane to a surface 2a of a metal substrate 2 and heating the first solution to form a first coating 1 on the surface 2a of the metal substrate 2, and a second step of applying a second solution containing a polysilazane to a surface 1a of the first coating 1 and heating the second solution at a temperature lower than a heating temperature in the first step to form a second coating 3 on the surface 1a of the first coating 1, wherein a density of the first coating is less than 2.00 g/cm3, and a density of the second coating is 2.00 g/cm3 or more.